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Things that Happened Before You were Born. (The earth and SWMM were created) a story by Dr. Larry A. Roesner, Ph.D.,P.E. based (loosely*) on biblical quotes and his own bigger than life experiences. *Actually very loosely. t 1. t 2. t 3. Rain over duration, Σ t.
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Things that Happened Before You were Born (The earth and SWMM were created) a story by Dr. Larry A. Roesner, Ph.D.,P.E. based (loosely*) on biblical quotes and his own bigger than life experiences *Actually very loosely
t1 t2 t3 Rain over duration, Σt Time of concentration, Σ t The earth and SWMM parallels In the beginning, there was the Rational Method Qpeak = C·I · A
The earth and SWMM parallels And darkness covered the drainage world because of the limited applicability of the Rational Method
The earth and SWMM parallels Then forward looking engineers said “let there be light” And so, they created more rational models • SCS TR20 and TR55 • HEC-1,2,3,4,5,6, and RAS • SWMM
Rainfall Increasing Imperviousness Runoff The earth and SWMM parallels • SCS Method accounts for initial soil moisture and time varying C • Runoff hydrographs can be computed
The earth and SWMM parallels • HEC model produces runoff hydrograph from rainfall hyetograph using unit hydrograph technique (Who knows the Schneider coefficient for a 30% pervious urban area? ) • Hydrologic routing produces channel flows • Hec 2 computes steady state backwater through maximum discharge profile
The earth and SWMM parallels • SWMM was to be the mother of all models • It would trace runoff from its point of origin, through the stormwater system to and through the receiving waters, computing flows and water levels • It would trace wet weather pollution from its point of origin to its final fate in the receiving waters
Concept of SWMM Rainfall hyetograph Watershed Data RUNOFF Q (t) C(t) Q (t) Inlets Transport System Data Transport System Data EXTRAN TRANSPORT Q (t) Outfalls Q (t) C(t) Point Source Loads Receiving Water System Data RECEIVE Q (t), C(t) in Receiving Water
The earth and SWMM parallels And so they rested, And so it was, and (most) Civil Engineers saw the models and they were good. for 30yrs!!?
R f(t) S W S I f(t) Q (t) SWMM Runoff Module
INTRODUCTION TO SWMM AND MIKE SWMM CE 580 Analysis of Urban Water Systems Session 10 – Sept 25, 2000
This presentation is an embellishment of the road culvert example contained in the Mike SWMM documentation. In order to see the results of road overtopping, the weirs at nodes 110 and 60 have been changed to box conduits. Three simuations were performed: o The "existing" condition: File name Exam11e.dat - culvert 110 diameter = 1.0 ft - culvert 60 diameter = 3.0 ft o The "existing" condition: File name Exam11p1.dat - culvert 110 diameter = 2.0 ft - culvert 60 diameter = 3.5 ft o The "existing" condition: File name Exam11p2.dat - culvert 110 diameter = 4.0 ft - culvert 60 diameter = 5.0 ft The first simulation shows severe overtopping of the road at both location, with prolonged backwater at junction 110. The second simulation shows much improvement, and the third simulation shows the problem fixed except for a small 15 minute overtopping of the the road at junction 110. Modifications by LAR 12/2/98
Camp Dresser & McKeeDanish Hydraulic Institute The power of two...
Danish Hydraulic Institute- a Consulting and Research Organization • Objectives: • to develop and apply advanced methods and technologies • within hydraulic and hydrological engineering • to provide specialised consulting services • to contribute to the technological development through • international research collaboration and through • transfer of know-how and technology
MIKE 11 • 1-D modeling system for rivers and channels • HD, AD, WQ, ST, FF, GIS • more than 400 users world-wide
MIKE 21 • a modelling system for estuaries, coastal waters and seas • more than one hundred users in 35 countries
MIKE SHE • an integrated hydrological modeling system • 3-D Groundwater movement, unsaturated zone, Solute transport, dynamic link to MIKE 11 • some 50 users in 10 countries
MIKE BASIN • Water Master Planning • use of available water resources • planning for future water developments • GIS • defining the network • evaluating results • integrated analysis with spatial data
LITPACK • an integrated modelling system for Littoral Processes And Coastline Kinetics • more than 60 users in 20 countries
Top of Overbank Top of Bank Culvert
Road Elev. Road Elev. Junction 110 Junction 60 Road Road Culvert Culvert
Road Elev. Road Culvert Junction 110
Road Elev. Road Culvert Junction 110
Road Elev. Road Culvert Junction 110
Road Elev. Road Elev. Junction 110 Junction 60 Culvert Culvert Road Road